Folding ruler



(No Model.)

J. E. DAVIS.

FLDING RU-LER.' 11\To."594,60'7. P/atented NOV. 30, 1897.

4.33 JZ. L

lll 2 |||||||||||||||||||||||llllluaeeuneunuz:1n mpv/fifa. l"fmmhlill!iI!!!Il!!!llllllllllllllllllll||||||||||||||| WLTNEEEES. cv x NITED STATES PATENT EEIcE.

JOHN E. DAvIS, OE CONWAY, NEW HAMPSHIRE, ASSIGNOE OE ONEHALE To EDWARD D. HOLMES, OE NEWTON, MASSACHUSETTS.

FOLDING RU LER.

SPECIFICATION forming part of Letters Patent No. 594,607, dated November 30, 1897.

- Application filed August 15., 1896. Serial No. 602,869. (No modeLl To @ZZ whom it may concern:

Be it known that I, JOHN E. DAVIS, a citizen of the United States, residing at Conway, in the county of Carroll and State of New Hampshire, have invented a new and useful Improvement in Rules, of which the following is a full, clear, and exact description, reference being had to the accompanying kdrawings, forming a part of this specication, in explaining its nature.

' The invention principally relates to the construction of the hinge connecting the two main sections or arms of a folding rule,where by square corners or angles, both inside and outside, are obtained and the rule is adapted to be used as a square.v Heretofore these rules, so far as I have been aware, have had their principal hinge so constructed as to project into the angle at 'the meeting-point of the two arms when brought to a right angle and also to leave a space or recess at the outer corner When in such position, and consequently when bent to such an angle the arms vdid not form a complete square either upon the outeredges or upon the inner edges. I am enabled to provide the rule with a complete square by changing the construction of the hinges and also by changing the widths of the two main arms, my construction requiring that vone of the arms be slightly Wider than the other.

I will nowdescribe the invention in connection with the drawings, wherein- Figure lis a view of my folding rule Opened to form a square. Fig. 2 is a detail view of the corner of the same enlarged. Fig. 3 is a view of the opposite part ofthe same part of the rule as that shown in Fig. 2. Fig. 4 is a view in horizontal section of the hinge and parts of the arms when therule is Wide open. Fig. 5 is a view in plan of one section or member of the hinge, and Fig. 6 is a view in plan of the other section or member. Fig. 7 is a plan view showing portions of the two members in alinement With each other toform a straight-edge.

The rule has the arms A A', which may or may not be pivoted at a a', respectively. The arm A is slightly wider than the arm A' and has a lip a2, which projects uponthe rabbeted edge c3 of the arm A. The two arms are connected by the hinge B, the part b of which is shaped as represented in Figs. 4 and 6-that is, it has the sections o' b2 shaped in plan as represented in Fig. 6 to provide extensions having the straight edges b3 b4, the ear b5 having the curved outer edge b and the straight edge 197, which is ata right angle to the edge bg. It will be seen that the said extensions o b2 embrace the reduced portion or tongue c of the member A' and when the members A Aare in alinement complete the continuity of the straight-edge, as shown iu- Fig. 7. Again', when the members A A are at right angles to each other (see Fig. 3) the said eX-v tensions b b2 lill out the outer angle of the try-square. The sections b b2 have between them a space b9, which receives the tongue or part'c of the hinge-section c. Thepart b also has the pivot-hole blo, which extends through both sections b' b2 and which is conntersunk or enlarged at each end. The part Z7 of the hinge also has the portions 1911 612, forming a recess 513, into which the end of the arm A extends, the arm being recessed at its end to fit the said recess 613 and to bring the sections bu Z912 flush with its two surfaces and the edges b3 bs in line with its longitudinal edges. The hinge-section c' has the straight ledges c2 c3 c4 and the ear c5, which has the curved edge c6 and the straight edge c7,which, with the edge c4, forms a right angle. The rule` also. has the pivot-hole cs. The part c `of the hinge-section extends between the two parts b b2 of the hingesection b and is united thereto by the pivot e. (See Fig. 4.) The hinge-section c' also has the parts o9 010, which form a recess c11 and provide means by which it is fastened or secured to the end of the arm A, said end being fashioned to enter said recess c11 and having its outer surfaces and edges in line with the outer surfaces ofthe said parts o9 010 and with the edges c2 c4K thereof.

It will be seen that with a hinge of this construction when the arms A A are brought to a right angle the edge b4 of the hinge-section b will be inline with the outer edge of the arm A' and that said edge and the edge h3 form a right angle which is continuous to the apex. It will also be seen that the edges o7 c7 of the ears b5 c5 are then at right angles with each other and that the edges bs c4 come together IOO and form a complete right angle to the apex or point on the inner side of the rule, thus enabling the members t0 be placed at right angies to each other very readily by securing a eoincidenceofthe edgesaforesaid. rlhepivot e has a head e', which is contained in one of the countersinks of the hole D10, and the other countersink holds a nut e2, which screws upon the threaded end of the pivot within the other countersink, and that this structure brings the attaching devices iiush or within the faces of the arm or member A. It is preferable that the two parts of the hinge should be united with some stress to prevent a too easy turning of one upon the other, as it is desirable that the two arms when brought to a right-angular relation should maintain that relation and not be easily moved from it. This may be done by causing the two parts 1)' b2 to bind upon the tongue c of the section c' with some stress by tightening the pivotscrew by turning it in its nut, in which case it may have a slot across either end tor the reception of a screw-driver, or the nut may be turned by any suitable means, or the nut may be so secured to one hinge member and the screw-pivot to the other that the act of turning the arms of the rule to a right angle will cause the screw to turn in the nut sufficiently to slightly close the two hinge-sections t0- gether and thereby hold the screw with some stress in their right-angular relation.

There may be upon the outer face of the rule lines g g' upon the hinge-sections 1) c', which will indicate when brought together that the arms occupy a true right-angular relation to each other.

The rule may be made entirely of metal, if desired, and it may bear any arrangement 0r form of graduating marks.

By the above construction it will be seen that I provide a rule which when its two members A A' are in longitudinal alinement will form a straight-edge (see Fig. 7) and when said members are placed at right angles to each other will form a square. In order to lock the members A A' so that they will form a perfect right angle, I provide the curved rib or extension for one of the members,whieh enters a corresponding recess f' in the other member.

It will be understood that the hinge is so constructed as to not only provide for a continuous edge forming a complete right angle at the corners when one part is at a right angle to the other, but that the parts may also be opened from their right-angular relation to a straight line.

Having thus fully described my invention, I claim and desire to secure by Letters lat ent of the United States l. A combined straight-edge and try-square comprising the two members A, A', adapted to be thrown into longitudinal alinement relative to each other to form a straight-edge, the ears b5, c, secured to said members A, A', said ears bein g provided with edges 117,0.7 which are at right angles to the edges 118 cr1 of the members A, A', said edges 117, c7, serving to indicate the proper angular position of said members A, A' with respect to each other to form a try-square, and a pivot-pin e passing through said ears.

2. A combined straight-edge and try-square comprising the member A having the cars 1f', said ears having the straight edge 1F; extensions 11', 112, formed on said member A; and the member A' having the tongue c provided with an ear portion o5 which is pivoted between extensions 1'1', 112 and is provided with a straight edge e7 at right angles to the body portion ol' the member, said straight edge c7 when brought into alinement with said straight edge 117 indicating the right-angle position of the members A, A', a pivot-pin e passing through ears 115 and c5, and a stop f on the face of ear o5 which engages a recess f' on one of the extensions of member A.

3. A eolnbined straight-ed ge and trysquare comprising the two lnembers A, A', both of which are rabbeted on one edge so as to close together, ears b5, c5, having cut-away portions to form right-angle straight edges D7, c7, a pivot-pin e passing through said cars, the pivotal end of member A' being reduced some distance from the hinge-joint to allow free movement of the extensions 1)', b2 formed on member A, said extensions 1), 1)' not only completing the continuity of the straight-edge when the members A, A' are in alinement, but also completing the outer angle of the try-square when the members are at right angles to each other.

JOHN E. DAVIS.

lVitnesses:

F. F. RAYMOND, 2d, J. M. DOLAN.

TOO 

